This paper presents a broadband GaN pseudo high-electron-mobility transistor (pHEMT) two-stage driver amplifier based on an enhanced feedback technique for wideband system. Through well-designed parameter values of the and matching structure circuit, relatively flat frequency response was obtained over wide band. Simultaneously, in order to reduce fluctuation current caused by environmental tem...

One of the major yield killers of power-amplifier PHEMTbased MMICs is fabricating a T-shaped gate with gate periphery of several tens of mm. We have investigated a novel PMMA/PMGI/PMMA tri-layer resist scheme for T-Gate definition of PHEMTs with 0.25-μm gate length and in-situ Ar ion beam treatment before gate evaporation as methods for eliminating this problem. We intend to extend this technol...

This paper analyzes the main factors limiting bandwidth expansion of low-noise amplifiers (LNA) and designs a broadband LNA with 2-40.5 GHz. The is designed using multiple methods, including cascode, resistance feedback, cascode Darlington amplifier. amplitude-frequency characteristics principle three structures are studied theoretically based on small-signal equivalent circuit model. Thanks to...

This paper presents a high-accuracy multifunction chip (MFC) with amplitude and phase control in X-band. The MFC is designed common leg structure incorporates 6-bit attenuator (ATT), shifter (PS), two gain compensation amplifiers (GCAs), three single pole double throw switches (SPDTs), fourteen logic circuits. interstage matching networks (IMNs) are inserted to compensate for the insertion atte...